This invention relates to a new and improved coupling which is utilized to interconnect a pair of conduits. More specifically, the invention relates to a coupling having a vent valve assembly for venting fluid pressure from the coupling and from conduits connected with the coupling upon manual actuation of the vent valve assembly.
The present invention is usable, as one example, in connection with the filling of relatively small tanks for gas appliances using LP gas, such as outdoor grills. Such tanks are typically filled from a supply tank having a supply hose with a plug assembly on its end. An operator telescopically inserts the plug assembly into a socket assembly connected with the small tank.
The operator then opens a valve on the small tank and a valve at the supply tank. Gas flows from the supply tank, through the supply hose, through the interconnected plug and socket assemblies, and into the small tank. When the small tank has been filled with the desired amount of gas, the valve at the small tank is closed. The valve at the supply tank is also closed. Thereafter, the plug assembly is disconnected from the socket assembly.
At the time the plug assembly is disconnected from the socket assembly, high pressure fluid is still present in the supply hose, in the plug assembly, in the socket assembly, and in a conduit between the socket assembly and small tank valve. This high pressure fluid is vented to atmosphere upon disconnection of the plug assembly from the socket assembly. The venting of high pressure fluid creates a potentially hazardous situation if the fluid is flammable. The high pressure in the system also tends to rapidly expel the plug assembly from the socket assembly.